Device for triggering a gas spring

ABSTRACT

A device for triggering a gas spring (b 1) with an actuating device ( 2 ) and an actuating member ( 4 ) operatively connected to the actuating device ( 2 ) and acting directly upon a terminal trigger ( 3 ) of the gas spring ( 1 ) is designed and constructed for a simple and reliable actuation with reduced triggering forces and an infinitely variable regulation of the extension speed and extended position such that the actuating member ( 4 ) is constructed as a force and/or distance reducing or multiplying lever arrangement ( 5 ), and that one of the levers—triggering lever ( 6 )—directly presses the trigger ( 3 )

BACKGROUND OF THE INVENTION

The invention relates to a device for triggering a gas spring with anactuating device and an actuating member that is operatively connectedto the actuating device and directly acts upon a terminal trigger of thegas spring.

Gas springs are known from practice in a great variety of types.Numerous gas springs comprise an integrated valve system, whereby thegas spring is infinitely variable and lockable in any position. In thisinstance, a piston is sealed against a pressure cylinder, and itseparates two gas chambers from each other. When the valve is closed,the gas spring is locked and facilitates a blocking in the desiredposition. By actuating a trigger, which is usually constructed as atriggering stem, the valve is opened, and the gas spring can bepositioned continuously. The extension speed and cushioning can becorrespondingly varied by the selection of the nozzle in the piston.

Gas springs of the type under discussion may be used in many ways. Knownfrom practice is the use of such gas springs in desk chairs. It islikewise possible to use gas springs for adjusting automobile seats orfor moving solaria. Even desks can be vertically adjusted by gassprings.

The gas springs known from practice require an actuating member whichoperatively connects to an actuating device and directly acts upon atrigger provided on the end side of the gas spring. For example, in thecase of desk chairs actuating members are used which are constructed inthe form of simple levers that normally push directly on a trigger in anend region. Such a configuration of the actuating member has theenormous disadvantage that nonetheless substantial forces are requiredfor triggering the gas spring. Added to this is the further disadvantagethat the triggering is only difficult to regulate proportionally, sothat in the case of considerable triggering forces an adjustment of thegas spring speed is practically not possible.

It is therefore the object of the present invention to design andconstruct as well as further develop a device for triggering a gasspring in such a manner as to permit a simple and reliable actuationwith reduced triggering forces and with an infinitely variableregulation of the extension speed and the extended position.

SUMMARY OF THE INVENTION

The above and other objects and advantages are achieved by the provisionof a device for triggering a gas spring which is designed andconstructed such that the actuating member is realized as a force and/ordistance reducing or multiplying lever arrangement, and that one of thelevers—triggering lever—directly pushes the trigger.

In accordance with the invention it has been recognized to depart fromthe triggering by means of a simple lever and design and constructinstead the actuating member such that a force and/or distance reductionor multiplication is obtained. To this end, a very special leverarrangement is provided, wherein one of the levers—triggeringlever—pushes the trigger. In other words, it is possible to regulatewith the lever arrangement the actuation of the trigger proportionally,so as to permit a regulation of the gas spring speed on the one hand andof the extended position on the other hand with the smallest possibletrigger forces of the gas spring.

In an especially advantageous manner, in particular with respect toespecially favorable conditions for reducing or multiplying force and/ordistance, the lever arrangement comprises an adjustment mechanism. Inconcrete terms, the lever arrangement may comprise an eccentric, a camdisk or cam, or a gear, or even a gearing. In any event, it is possibleto design and construct the lever arrangement for a force and/ordistance reduction or multiplication in any desired manner. What mattersprimarily is that the trigger forces are reduced.

In concrete terms, the triggering lever could be jointed at its one endfor pivotal movement about a stationary axis of rotation. At its otherend, it could be connected to a second—connecting lever—for rotationabout the end thereof. The connecting lever again could be connected atits other end for rotation to a third lever—actuating lever. Thisactuating lever could again be jointed at its one end for pivotalmovement about a stationary axis of rotation and be operativelyconnected at its other end with the actuation device. As a whole, withinthe scope of such a configuration three levers are provided, which favora reduction of the trigger force at a corresponding ratio of the leversections of the triggering lever on the one hand and the actuating leveron the other hand. More specifically, it would be possible topredetermine the extent of the force and/or distance reduction ormultiplication based on the ratio of the lever sections, namely on theone hand of the triggering lever between the stationary axis of rotationand the trigger as well as between the trigger and the pivotalconnection with the connecting lever, and on the other hand of theactuating lever between the stationary axis of rotation and pivotalconnection with the connecting lever, as well as between the pivotalconnection with the connecting lever and the free end or operativeconnection with the actuating device.

As regards a concrete arrangement of the actuating member, same may bealigned with the gas spring and arranged in a frame adjacent thetrigger. The frame itself could comprise a total of four, in thisinstance preferably freely extending frame posts for receiving in pairsthe stationary axes of rotation.

Furthermore it will be especially advantageous, when the frame isdimensioned such that it is inserted together with the gas spring in apreferably tubular casing. At the free end of the frame, a cover couldclose the casing, so that the entire casing is closed on the actuationside.

As previously mentioned, the actuating device acts upon the trigger,directly or indirectly, via the actuating member. Within the scope of afirst possible configuration, the actuating device could act upon theactuating member electrically, preferably via a miniaturized servomotoror stepping motor. Within the scope of a second possible configuration,the actuating device could act upon the actuating member by induction.According to a third possible configuration, the actuating device couldact upon the actuating member via a magnet, such as an electricallyoperating lifting or printer magnet. Likewise, it would be possiblewithin the scope of a further possible configuration to cause theactuating device to act upon the actuating member hydraulically orpneumatically. Finally, with respect to a particularly simpleconfiguration of the device in accordance with the invention, it will beof advantage, when the actuating device acts upon the actuating membervia a cable line or Bowden cable.

Should a Bowden cable be provided, same could be jointed at its end tothe actuating lever. When being pulled, the cable could pivot theactuating lever in direction of the trigger, extend through the frame,preferably inside the casing along the gas spring, emerge from thecasing at the end opposite to the trigger, and finally extend via guideelements to the actuating device.

For a simple release, the actuating device comprises a lever, knob, orthe like. Should a Bowden cable be used, the actuating device couldcomprise a lever that receives the Bowden cable at its end. In anyevent, it is easy to engage the actuating member via such a lever, sothat complicated constructions are not needed.

There exist various possibilities of improving and further developingthe teaching of the present invention. To this end, one may refer to thefollowing description of an embodiment of the invention with referenceto the drawing. In conjunction of the description of a preferredembodiment of the invention with reference to the drawing, alsogenerally preferred configurations and further developments of theteaching are explained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic sectional side view of an embodiment of the devicein accordance with the invention when the trigger of the gas spring isnot operated, the Figure showing only the actuating member and thetrigger;

FIG. 2 is a schematic sectional side view of an embodiment of the devicein accordance with the invention when the trigger of the gas spring isoperated, the Figure showing only the actuating member and the trigger;

FIG. 3 is a sectional side view of the frame of the actuating memberwithout the lever arrangement; and

FIG. 4 is a sectional view of the embodiment of FIG. 3 along the lineIV—IV.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The Figures illustrate a device for triggering a gas spring 1, of whichonly an end side is shown. The device comprises an actuating deviceschematically indicated at 2 and an actuating member 4 that isoperatively connected to the actuating device 2 and acts upon a terminaltrigger 3 of the gas spring 1.

In accordance with the invention, the actuating member is 4 is realizedas a force and/or distance reducing or multiplying lever arrangement,wherein one of the levers, a so-called triggering lever 6 directly actsupon the trigger 3.

FIGS. 1 and 2 show very clearly that the triggering lever 6 is jointedat its one end for pivotal movement about a stationary axis of rotation7. At its other end, it is connected for rotation to the one end of asecond lever, the so-called connecting lever 8. With its other end, theconnecting lever 8 is connected to a third lever, the so-calledactuating lever 9. At its one end, the actuating lever 9 is jointed forpivotal movement about a stationary axis of rotation 10. At its otherend, it is operatively connected to the actuating device 2.

The extent of force and/or distance reduction or multiplication ispredetermined by the ratio of the lever sections, namely, on the onehand, of the triggering lever 6 between the stationary axis of rotation7 and trigger 3 as well as between the trigger 3 and the pivotalconnection to the connecting lever 8, and on the other hand of theactuating lever 9 between the stationary axis of rotation 10 and thepivotal connection to connecting lever 8 as well as between the pivotalconnection to connecting lever 8 and the free end or operativeconnection to the actuating device 2.

As can be noted from all Figures, the entire actuating member 4 is inalignment with the gas spring 1. Furthermore, the actuating member 4 isarranged in a frame 11 adjacent trigger 3. The frame 11 has a total offour posts 12 that freely extend at the end side and are used forreceiving in pairs the stationary axes of rotation 7 and 10.

Together with the gas spring 1, the frame 11 is inserted into a tubularcasing 13, which is closed by a cover 14 at the free end of frame 11.

As regards a particular actuation or configuration of the actuatingdevice, the general description is herewith incorporated by referencefor purposes of avoiding repetitions. In the selected embodiment, theactuating device 2 operates the actuating member 4 via a Bowden cable15. The Bowden cable is jointed to the end of actuating lever 9 andpivots, when being pulled, the actuating lever 9 in the direction oftrigger 3. The Bowden cable extends through the frame 11 inside casing13 along the gas spring 1, and emerges from the casing 13 on the sideopposite to or facing away from the trigger 3. Finally, the Bowden cable15 extends via only indicated guide elements 16 to the actuating device2. The latter may be provided for a triggering with a kind of actuatinglever 17.

Finally, it should be explicitly pointed out that the above-describedembodiment serves only to discuss the claimed teaching, without howeverlimiting same to this embodiment.

What is claimed is:
 1. A device for triggering a gas spring having atrigger which is moveable between a locked position and a releaseposition and comprising a triggering lever having one end mounted forpivotal movement about a first fixed axis and positioned for engagementwith said trigger at a medial location along the length of saidtriggering lever, a connecting lever pivotally connected at one endthereof to an opposite end of said triggering lever, an actuating leverhaving one end mounted for pivotal movement about a second fixed axis,with the actuating lever having an opposite free end, and with theconnecting lever being pivotally connected to the actuating lever at alocation intermediate the ends of the actuating lever, and an actuatingdevice for moving said opposite free end of said actuating lever so asto cause said triggering lever to engage and move said trigger towardone of said locked and release positions.
 2. The device as defined inclaim 1 wherein the triggering device is configured as a force and/ordistance reducing or multiplying lever arrangement, with the reducing ormultiplying lever arrangement being defined by 1) the ratio of thedistance between the first fixed axis and the trigger, and the distancebetween the trigger and the pivotal connection between the triggeringlever and the connecting lever, and 2) the ratio of the distance betweenthe second fixed axis and the pivotal connection between the connectinglever and the actuating lever, and the distance between the pivotalconnection between the connecting lever and the actuating lever and theopposite free end of the actuating lever.
 3. The device as defined inclaim 2 wherein said actuating device comprises a cable having one endfixed to said opposite free end of said actuating lever, so that when anopposite end of the cable is pulled it pivots the actuating lever in thedirection of the trigger.
 4. The device as defined in claim 2 furthercomprising a frame enclosing said triggering device and at least aportion of the gas spring which includes the trigger, with said frameincluding bores which define said first and second fixed axes.
 5. Thedevice as defined in claim 2 wherein said first and second fixed axesare parallel to each other and disposed on opposite sides of thetrigger.
 6. The device as defined in claim 5 wherein the first andsecond axes are spaced from each other in an axial direction which isdefined by the movement of the trigger.
 7. The device as defined inclaim 6 wherein the actuating lever generally overlies the triggeringlever on the side thereof opposite the trigger.